Centerless grinder



AMay 24; 1932. H, HQEG 1,859,443

` cENTERLEss GRINDER Filed Dec. 18, 1928 2 Sheets-Sheet l May 24, 1932. H. J. HoEG CENTERLESS GRINDER' Filed Dec. 18, 1928 2 Sheets-Sheet 2 Patented May 24, 1932 UNITED t 4s'mxrl-:s

HENRY JAMES Hons, or s'r. CLAIR snomss, MICHIGAN Y CENTERLESSGRINYDER y Aplication led December 18, 1928; Serial-'No'. 326,884.6. A

This invention relates to centerless grinding machines and particularly to a device for use therewith for improving the character of the work produced in such machines.

The conventional type of centerless grinding machine comprises a rapidly rotatable grinding wheel and a slowly rotatable feed wheel together with a bevelled blade for properly positioning the workin its passage lo between the grinding wheel and the feed wheel. The peripheral edges of the grinding wheel and feed wheels are positioned in opposed relation and the axis of the feed wheel is skewed relative to the axis of the grinding i5 wheel in order to cause the work to rotate and move in an axial direction between the wheels. It has been found in practice that inasmuch as the work is not rotating as it enters the grinding zone a nick is, formed in Z0 the work which the grinding loperation fails to remove. This nick is very objectionable in various vtypes of work, such as wristpins for automobile engines, and while the defect is sometimes quite diiiicult to see, it is easily found with an amplifying gauge. A similar result occurs when the work leaves the grinding zone due to the discontinuation of its rotation.

It is an object ofthe present invention to overcome this difficulty, and with this in view the invention contemplates the provision of means for causing the work to rotate as it is fed into, and to maintain its rotation as it V leaves the grinding zone. f Before explaining in det-ail ythe present invention, it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of lother embodiments and of being practiced or carried out in various ways. Also it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation, and it is not intended to limit the invention beyond the terms of the several claims hereto appended as considered in View of the prior art and the requirements thereof.

The invention will be more clearly understood from the following description in conjunction vwith the accompanying drawings; in which Fig. 1 is an elevational viewof 'a centerless grinding machine embodying the invention; Y -V Fig. 2 isa plan view of the same ;H

Figs. 3 and 4 are sectional views taken upon the lines 3 3 and b4, respectively of Fig. 1; yand Fig. 5 is a detail view of the work, such as a wrist pin for an automobile engine.

The embodiment of the invention'illustrated in the accompanying 4drawings comprises a: main frame 10 carrying bearings (not 65 p shown) for rotatably mounting a grinding Y wheelv 11' and a feed wheel 12 with the axis of the feed wheel skewed relative to the axis of the grinding wheel. A frame 15 is secured upon the frame 10, as by bolts 16, so as to 0- extend to oppositesides of the grinding and feed wheels and is provided at each end thereof withV upright members 17 adjacent the Hat faces of the wheels.l The uprights 17 are connected by a member which in the form illustrated is provided with a central longitudinal groove 51 adapted to receive and support a Vwork positioning blade 52 havingan upper bevelled surface 53 which extends longitudinally between the grinding wheel 11 and feed wheel 12 to a point beyond the opposite flat faces thereof. `Eachof the uprights 17 is provided with vertical grooves-18 and 19 in its front VVand rear faces respectively. yAn arm 2() is pivotally mounted within the groove 18 upon a pin 22 fixed in the upright 17 and is provided with a rearwardly extending lug 25 Vhaving a V-Shaped notch 26 adapted to receive the end of an adjusting screw 27 mounted in the upright 17. The notched lug 25 on the arm 2O is held against the adjusting screw 27 by aspring 30 having one end vsecured to one end of the arm 20 and its OtherV end secured to a bolt 31-held in a bracket 32 extendingforwardly from the upright 17 The upper end of the arm 20 is provided with an inclined guide opening adapted to receive an arm 56 which is held in any desired position therein by a setscrew 57.- The upper end of the arm 56 is provided withbearings w in which is rotatably mounted a shaft 58 carrying a roll 59 arranged with its axis parallel to the aXis of the grinding wheel. A plate having an upwardly extending portion 61 is secured upon the top surface of the arm 20 as by screws 62. An inclined feed trough extends downwardly to apointadjacent one end of theblade 52 for f eedingpieces of work lV, such as Wrist pins for automobile engines successively' upon the bevelled surface 53.Y w v An arm is pivotally mountedwithin the groove 19 upon a pin 36 in the upright 17. An adjusting screwvf isprovided in ,the arm 35 to extend downwardly from a portion thereof to engage anotch 38 in a lug 39- ein tendin-gfrearwardly V; from.l the upright 17;

The end of the adjusting screw 37 is held in enga-gement with ,thenotched lug S9-by a spring 40 .one end of-'which is attached to the end of the arm`35 and the other end .of which is secured --to. a. Apin 41; eXtendingupwar-dly throughgan.. openi1ig4l2-i n the uprightfl A` hardenedplate 43 iissecured to, .they front C' face of the arm 35 adjacent theupper end l workVy are thenplaced. inthe trough 65 and are carriedby their` own weight .successively upon bevelled sur-face v53 of the blade 52 so as tofrest .against'the surface ofthe/plate 43 which is arranged to engage the work alonga line .parallelto the axisofvthe grinding wheel andpositio-nitina `path forits passage loetween the.grinding.wheel. and' feed wheel. The; weight ofthe column of successive pieces ofworkin t-,hetrough 65 causes-the work to move betweenthe, plate 43 vand the roll 59V whereupon the latter maintains engagement between the work and the feed wheel; to .cause the work to rotate `as itis moved'past the edge of thegrinding Wheeli It. will be. understood the roll591 yand plate43 may-be provided for controllingT the position and rotation ofthe.

work asit enters orleaves the grinding zone.

lthasbeen found thattheobjectionable nick formedin.. thework can be eliminated by.V

controlling thework so las to position it properly and maintain its rotation as it moves into and leavesthe grinding zone.

Y l. In a centerlessf grindingvmachiner'the combination of a grinding-wheel, a feed wheel,

afblade for positioning lthe, work -between the wheels, means for causing the work .to;rotate afs-.1t Imoves i past/the edge of the grinding,-

that either or both.v

combination lof a grinding wheel, a feed. "wheel,fa'blade for positioning the work between thewheels, means for causing the work torotate as it moves past the edge of the grinding wheel .including an armv pivotally mounted adjacent one of said wheels7 a roll ino-untedon said arm adaptedto hold the work in engagementfwithf.said feedl wheel `while substantially out'of` Contact with-'sad grindingwheel as the-workmoves past the edgeof said. grindingwheel, astop, and means for adj usting the position of vsaid Aroll-rela@ tivel tof said blade. Y

Ina grindinglmachine, the'combination of a. grinding wheeland. a: feedwheel-sotarranged as tov feed` work. axiallyy therebetween; a clade j for, positioning `work betweensaid wheels, a member `mounted on-one=side-of saidY blade adjacent saidfeed -wheel, aaroll mounted on the other :side ofsaid bladaad jacent ysaid grinding gwheehsaid member :and said roll cooperatingwith said blade'to align thework in a path; for passagebetweensad Wheels and hold the work in engagementlwith said feed wheell while ksubstantially outof Contact with said grindingwheel as itmoves past-.the edge of ysaidgrinding wheel and means `for mountingsaid rollvfor yielding movement away fromsaid membera ln testimony whereof 'I .si-gnature.

HENRYV JAMES' fir-ione. 

